北乌头 bei wu tou

Caudex conical or carrot-shaped, 2.5--5 cm, 7--12 mm in diam. Stem (65--)80--150 cm, usually branched, glabrous, with leaves equally arranged along stem. Proximal cauline leaves withered at anthesis, middle ones shortly to long petiolate; petiole 3--11 cm, glabrous; leaf blade pentagonal, 9--16 × 10--20 cm, papery or subleathery, abaxially glabrous, adaxially sparsely retrorse pubescent, base cordate, 3-sect; central segment rhombic, apex acuminate, subpinnately divided or lobed; lateral segments obliquely flabellate, unequally 2-parted. Inflorescence terminal, 9--22-flowered; rachis and pedicels glabrous; proximal bracts 3-fid, others oblong or linear. Proximal pedicels 1.8--3.5(--5) cm, with 2 bracteoles at middle or below; bracteoles linear or subulate-linear, 3.5--5 × ca. 1 mm. Sepals purple-blue, abaxially sparsely retrorse pubescent or nearly glabrous; lower sepals oblong, 1.2--1.4 cm; lateral sepals 1.4--1.6(--1.7) cm; upper sepal galeate or high galeate, 1.5--2.5 cm high, shortly or long beaked, lower margin ca. 1.8 cm. Petals glabrous; limb 3--4 mm wide; lip 3--5 mm; spur incurved or subcircinate, 1--4 mm. Stamens glabrous; filaments entire or 2-denticulate. Carpels (4 or)5, glabrous. Follicles erect, (0.8--)1.2--2 cm. Seeds ca. 2.5 mm. Fl. Jul--Sep. 2n = 32*.

Grassy slopes, grasslands, forests, forest margins, by streams; 2000--2400 m. Hebei, Heilongjiang, Jilin, Liaoning, Nei Mongol, Shanxi [Korea, Russia (Siberia)].

One of us (Kadota) indicates that plants with pubescent pedicels named Aconitum kusnezoffii var. crispulum W. T. Wang and A. kusnezoffii var. pilosum Y. Z. Zhao, nom. inval., are hybrid derivatives between A. kusnezoffii and other species. Those of var. crispulum have glabrous rachises and upper stems and apically retrorse pedicels, and occur in Hebei, Heilongjiang, Jilin, and Liaoning. Those of var. pilosum have appressed and retrorse pubescent or subglabrous rachises, upper stems, and pedicels, and occur in Nei Mongol.